Ever since the FDA approved the human papillomavirus (HPV) vaccine in 2006, its introduction has been embroiled in a medical, social, cultural, and political controversy. This controversy has once again been rekindled in the recent Republican primary debates between Texas governor Rick Perry and Congresswoman Michele Bachmann from Minnesota, in which Bachmann emphatically stated that Merck's HPV vaccine, Gardasil, causes mental retardation.

As a physician, parent, and author of the award-winning book The HPV Vaccine Controversy: Sex, Cancer, God and Politics (Praeger, 2008), I feel compelled to comment on this issue.

A report presented by four different sources to the Advisory Committee on Immunization Practices (ACIP), an independent panel of experts that advises the Centers for Disease Control and Prevention (CDC) on vaccine policies, found no signals to link Garda­sil directly to any of the serious adverse effects that have been publicized in the media.

To clarify this and help consumers make the best-informed decision be­fore vaccinating, it is helpful to understand the difference between a side effect (caused directly by the vaccine) and an adverse effect (which usually occurs within six weeks after the administration of a vaccine but may or may not be related to the vaccine).

1) The most common side effects reported are pain followed by swelling and redness at the site of injection. These temporary symptoms usually resolve within a few days, as is the case with most other vaccines.

2) The number of adverse effects that link the HPV vaccines to the nervous system disorder Guillain-Barré Syn­drome is around one to two out of every 100,000 cases-about the same as the number of cases that occur in the general population as a sheer coincidence or chance-and such disorders have the same statistical occurrence as the population at large that has not been vaccinated.

It is obvious that the greater the number of shots administered (as of June 22, 2011, 35 million doses of Gardasil had been distributed), the more likely the chance for these rare and unexpected events to occur. It should be noted that there is no report from the CDC of Gardasil resulting in mental retardation.

The HPV vaccine has established a decent track record at five years post-licensure. Based upon these current findings, the FDA strongly recommends vaccinating the target population: nine- to twenty-six-year-old females and males. The CDC will continue to be vigilant and monitor safety data on an ongoing basis. Nevertheless, it is helpful to remind ourselves that regardless of how well studies are conducted, gray zones of risk exist. The history of medicine has shown us that such unfortunate events do occur for unknown reasons, and research is underway to study if genetics and environmental factors have a role to play in such rare and serious events.

One should always balance the great­er good with these potentially minimal risks when evaluating the ad­vantages offered by new and emerging medicines. Scaremongering for personal political gain does not bode well for the education and welfare of the public. In the case of the HPV vaccine, it would be a shame if negative attention created by a few rare effects hampers the efforts to reach millions of women and men who risk losing their lives to HPV-related diseases, including cancers and particularly cervical cancer, both in our country and around the world.

Herbal medicines are currently quite popular; consumers are spending billions on them each year. Enthusiasts praise them as natural and safe, while skeptics often see them as little more than glorified placebos. The general public is frequently confused by such controversies, by a plethora of misinformation, and by the bewildering categories of medicines derived from herbs (U.S. Government Accountability Office 2010). Here I will try to clear up some of this confusion by explaining what the different categories are.

Herbal Medicines

Herbal medicines are preparations made from whole plants or whole parts of plants. They are also called botanical medicines, remedies, or supplements. Invariably they contain a mixture of ingredients, some of which may be pharmacologically active. Frequently they are marketed as dietary supplements, which are not required to have proven efficacy, safety, or quality in the United States and most other countries (Marcus and Grollman 2002, 347). Thus the spectrum is wide with both high- and low-quality products often placed side by side. Calls for tighter regulation are made regularly (e.g., U.S. Government Accountability Office 2009) but are routinely frustrated.

Herbal medicines are mostly used by consumers for self-treatment of minor symptoms. Doctors rarely employ them (except in some countries, such as Germany) and, crucially, traditional herbalists use an entirely different approach with each treatment.

The majority of herbal medicines have not been scientifically tested. But some have been adequately analyzed, standardized, and submitted to clinical trials (Ernst et al. 2006). St. John's Wort (Hypericum perforatum) is perhaps the best-investigated example. We know that this herbal antidepressant has several pharmacologically active ingredients that have been standardized in high-quality products and tested for efficacy and safety in approximately fifty clinical trials and many post-marketing surveillance studies. The results leave little doubt that St. John's Wort is efficacious for mild to moderate depression. It is also relatively safe as long as it is not combined with other drugs (Ernst et al. 2006).

When taken together with other medications, St. John's Wort can powerfully interact such that it lowers the plasma level of many drugs (Izzo and Ernst 2001, 15) which, of course, can have serious consequences. Thus the example of St. John's Wort goes some way toward demonstrating that herbal medicines can do both good and harm to patients. In other words, some herbal medicines are complicated pharmacological treatments and are biologically plausible (Schulz and Hänsel 2003).

Many other herbal medicines are not well-researched; therefore we cannot be certain about their risk-benefit profile (Ernst et al. 2006). Even the well-researched examples like St. John's Wort should be approached with healthy skepticism: the few high-quality products available are outnumbered by supplements of low quality and dubious content. Thus the market of herbal medicines is littered with products that contain little or no herbal ingredients (Sievenpiper et al. 2004, 27), are adulterated with prescription drugs (Miller and Stripp 2007, 9), or are contaminated with heavy metals (Buettner et al. 2009, 24; Cohen 2009, 361).

Synthetic Drugs Derived From Herbs

Many of our modern drugs (e.g., aspirin, Morphium, Tamoxifen, Vin­cris­tin, etc.) were originally derived from botanical material. In fact, many skeptics wonder why we cannot also extract and synthesize the active ingredients from well-researched herbal medicines such as St. John's Wort and generate single ingredients derived from that plant. This would clearly solve several problems inherent in herbal medicine, such as standardization.

While this approach of creating pure compounds does work occasionally, it fails in other instances. One reason can be the fact that herbal medicines tend to have not one but a multitude of pharmacologically active ingredients. Thus extracting only one ingredient might reduce the pharmacological activity of the whole plant extract.

Single ingredients derived from herb­al extracts can no longer be considered herbal medicines as, by definition, herbal medicines are based on the whole plant. Nevertheless, such drugs are reminders of the fact that many plants contain molecules that are pharmacologically active and can thus have both beneficial and detrimental health effects.

Traditional Herbalism

If a patient consults a Chinese, Indian, Japanese, or European herbalist, he will be diagnosed and treated according to obsolete and untested principles of diagnosis, pathophysiology, and so forth. Treatment will typically be individualized according to the characteristics of each patient and based on complex, tailor-made herbal mixtures of several (up to ten) herbal extracts. This means that ten patients suffering from depression may receive ten different, individualized concoctions, none of which might contain St. John's Wort, the only evidence-based herbal antidepressant. In other words, the biological plausibility of traditional herbalism is questionable.

Traditional herbalism is thus dramatically different from the herbal medicine described above. To scientifically test its value can be complex but it is doubtlessly possible. Few rigorous studies of this approach are currently available, and those that have been published do not support the notion that traditional herbalism is effective (Guo et al. 2007, 83).

Neither can we be certain about its safety. Because the tailor-made concoctions of traditional herbalists may contain a confusing number of active ingredients, the potential for toxicity, herb-drug interaction, contamination, and so on can be considerable. More vigorous regulation of herbalists, a subject currently being discussed in Europe (Hawkes 2010, 339), is therefore required.

Homeopathic Remedies

The public frequently confuses homeopathy with herbal medicine. The error usually arises because many homeopathic remedies are produced from "mother tinctures," which are based on herbal extracts. Thus they can carry the same (or similar) names as herbal products. The difference is that homeopathic remedies are typically highly diluted and therefore contain no active ingredients at all. Thus homeopathy lacks any biological plausibility.

Arnica is a good example. It is used as an herbal cream as well as a homeopathic remedy. Because it is toxic, Arnica should not be taken as an oral herbal medicine. Being highly diluted, homeopathic Arnica is, of course, both nontoxic and entirely ineffective (Ernst and Pittler 1998, 133).

Bach Flower Remedies

These products are currently very popular for self-medication, particularly in Europe. They are produced by placing freshly picked flowers in spring water. Thus they are also plant-derived and frequently confused with herbal medicines. After the flowers have floated for a while, the water is mixed with brandy and sold at high prices as Bach Flower Remedies.

Bach Flower Remedies were developed by the British physician Edward Bach, who had previously worked as a homeopath. His remedies have, however, little in common with homeopathy except, of course, that they are neither biologically plausible nor of proven effectiveness for any condition (Ernst 2010, 140).

Anthroposophical Medicines

Rudolf Steiner developed his anthroposophical medicines about one hundred years ago (Ernst 2008, 150). They are produced according to protocols similar to those of homeopathic remedies. Unlike homeopathy, however, anthroposophical medicine does not follow the "like cures like" principle.

As many anthroposophical medicines are based on plants, they are also often confused with herbal medicines. The best known example is Iscador®, a fermented mistletoe preparation that is a highly popular treatment for cancer in Europe. Numerous trials exist, but collectively their results do not show that this is an effective therapy (Horneber et al. 2008, 16).

Conclusion

Many articles on herbal medicine conclude by stating that more research is needed. Between 1999 and 2007, the National Institutes of Health has spent US $1.9 billion on research into dietary supplements (Regan, Wambogo, and Haggans 2011, 141). Not all of this money was well invested (Ernst et al. 2011). I therefore advocate not necessarily more research but better-designed studies into the few plausibly beneficial aspects of herbal medicine. n

References

Buettner, C., K.J. Mukamal, P. Gardiner, et al. 2009. Herbal supplement use and blood lead levels of United States adults. Journal of General Internal Medicine 24(11): 1175-82.

Cohen, P.A. 2009. American roulette: Con­taminated dietary supplements. New Eng­land Journal of Medicine 361(16): 1523-25.

Ernst, E. 2008. Anthroposophic medicine: A critical analysis [in German]. MMW Fortschritte der Medizin 150(Suppl. 1):1-6.

---. 2010. Bach flower remedies: A systematic review of randomised clinical trials. Swiss Medical Weekly 140: w13079.

Ernst, E., and M.H. Pittler, 1998. Efficacy of homeopathic arnica: A systematic review of placebo-controlled clinical trials. Archives of Surgery 133(11): 1187-90.

Ernst, E., M.H. Pittler, B. Wider, et al. 2006. The Desktop Guide to Complementary and Alternative Medicine, 2nd ed. Edinburgh: Elsevier Mosby.

Ernst, E., S.K. Hung, and Y. Clement. 2011. NCCAM-funded RCTs of herbal medicines: An important critical assessment. Perfusion 24(3) 89-102.

Guo, R., P.H. Canter, and E. Ernst. 2007. A systematic review of randomised clinical trials of individualised herbal medicine in any indication. Postgraduate Medical Journal 83(984): 633-37.

Hawkes, N. 2010. A spanner in the herbal works. BMJ 339: b5441.

Horneber, M.A., G. Bueschel, R. Huber, et al. 2008. Mistletoe therapy in oncology. Cochrane Database Systems Review 16(2): CD003297.

Izzo, A.A., and E. Ernst. 2001. Interactions between herbal medicines and prescribed drugs: A systematic review. Drugs 15: 2163-75.

Marcus, D.M., and A.P. Grollman. 2002. Botanical medicines: The need for new regulations. New England Journal of Medicine 347(25): 2073-76.

Miller, G.M., and R. Stripp. 2007. A study of western pharmaceuticals contained within samples of Chinese herbal/patent medicines collected from New York City's Chinatown. Legal Medicine 9(5): 258-64.

Regan, K.S., E.A. Wambogo, and C.J. Haggans. 2011. NIH and USDA funding of dietary supplement research, 1999-2007. Journal of Nutrition 141(1):1-3.

Schulz, V., and R. Hänsel. 2003. Rational phytotherapie: A physician's guide to herbal medicine, 5th ed. Berlin: Springer-Verlag.

Sievenpiper, J.L., J.T. Arnason, E. Vidgen, et al. 2004. A systematic quantitative analysis of the literature of the high variability in ginseng (Panax spp.): Should ginseng be trusted in diabetes? Diabetes Care 27(3): 839-40.

U.S. Government Accountability Office. 2009. Dietary Supplements: FDA Should Take Further Actions to Improve Oversight and Consumer Understanding. United States Accountability Office, January: Report to Con­gressional Requesters. GAO-09-250. Available online at www.gao.gov/new.items/d09250.pdf.

---. 2010. Herbal Dietary Supplements: Examples of Deceptive or Questionable Marketing Practices and Potentially Danger­ous Advice. United States Govern­ment Accountability Office, May 26: Testimony Before the Special Commitee on Aging, U.S. Senate. GAO-10-662T. Available online at www.gao.gov/new.items/d10662t.pdf.

When we think of conflicts of interest, we almost automatically think of money. In my area of research, complementary alternative medicine (CAM), there is no money—well, almost none (contrasted with most areas of mainstream medicine). Despite this fact, conflicts of interest are rife in CAM research. I am, of course, talking about a different type of conflict: the one that is created by strong belief and evangelic conviction.

Across the globe, I personally know many individuals who are full-time CAM researchers. They have different personalities, backgrounds, and skills. But they all have, as far as I can see, one characteristic in common: they are strong believers in the benefit of at least some aspects of CAM. On the one hand, this may seem entirely reasonable: if one didn’t believe in CAM, why would one dedicate one’s career to investigating it?

On the other hand, if the vast majority of CAM researchers are made up of CAM believers, things might not be quite right either. In other areas of medical research, the situation is—in my experience—very different. I know many pharmacologists, for instance, who are keenly aware of the dangers of medicines and extremely critical of some of the activities of the pharmaceutical industry. I cannot say that I know many CAM researchers who are truly concerned about the dangers of CAM or of the activities of those individuals or organisations that promote CAM uncritically.

Conflicts of interest are precarious because they tend to cloud judgment and generate bias—the type of bias that creeps in unnoticed and cannot be readily identified when studying a published paper. After some detective work, we might be able to find out, for example, that a certain paper that draws positive conclusions about the homeopathic remedy Traumeel® (Schneider et al. 2008) was coauthored by at least one “expert” who is on the payroll of the manufacturer of that very remedy—even if the paper itself fails to disclose this fact (Schneider et al. 2008). But what about more subtle yet potentially powerful conflicts of interest? I fear that they have far too much impact on CAM.

If the totality of researchers in one field is open to unidirectional bias, one has to worry about the area as a whole. The danger, then, is obvious: the field will collectively lose its balance and make serious and repetitive mistakes without even noticing them. In the absence of criticism “from the inside,” such an area of research can neither prosper nor mature. In my experience, CAM has very little internal criticism, as the following examples suggest.

Chiropractic

After the British Chiropractic Association (BCA) sued science writer Simon Singh for libel, the United Kingdom’s General Chiropractic Council (GCC, the regulatory body of its members) was inundated with about 700 complaints from skeptical bloggers about chiropractors who had made similarly bogus therapeutic claims. The GCC reacted by commissioning North American chiropractors to write an “evidence report.” Presumably, the GCC hoped that the report could clarify the evidence regarding the disputed claims. Bronfort et al.’s (2010) published report revealed no strong evidence for “manual therapies.” Despite this seemingly critical stance, the report is still not critical enough, in my opinion. The reason becomes clear upon a reading of its fine print. Even though the authors repeatedly mention the “quality of the evidence,” they fail to formally evaluate it. Thus, poor-quality primary studies are taken at face value, which inevitably leads to false-positive conclusions. Without the very obvious conflict of interest (chiropractors commissioned by the GCC), the report might have been far more critical than it turned out to be.

A similar situation occurs with systematic reviews of chiropractic as a treatment for specific conditions. Such articles are now emerging regularly, and they tend to display interesting discrepancies. For example, a review on the subject of asthma written by four chiropractors concluded that “chiropractic care showed improvement in subjective measures . . .” (Kaminskyj et al. 2010). Meanwhile, my own review, which included a critical assessment of the quality of the primary data, stated that “spinal manipulation is not an effective treatment for asthma” (Ernst 2009). Here I should mention perhaps that I, as an independent academic, have no conflicts of interest and receive no payments from Big Pharma or similar institutions that might have an axe to grind.

Years ago, I had already noted that reviews published by chiropractors tend to arrive at positive conclusions while those by independent experts do not (Ernst and Canter 2006). The explanation for this phenomenon seems to be simple: conflict of interest.

Acupuncture

Vickers et al. (1998) and others (Tang, Zhan, and Ernst 1999) have shown that 100 percent of all acupuncture trials originating in China report positive results. Recently, an in-depth analysis of acupuncture articles published between 1991 and 2009 revealed that China is now producing more acupuncture research papers than any other country (Han and Ho 2011). To make matters worse, this analysis also names the journals that publish the bulk of these articles: unsurprisingly, they tend to be the ones I have previously identified as publishing virtually no negative results (Ernst and Pittler 1997). Thus there is reason to fear that we are currently exposed to a mountain of research on acupuncture, much of which might be less than reliable.

Here the explanations might be more complex, and there could be more than one factor at play. Yet I have little doubt which one is the most important: conflict of interest.

What Can Be Done?

My message is clear: non-financial conflicts of interest can be just as powerful as financial ones, and in my area of research they seem to be quite overpowering. This problem will inevitably lead to significant distortions of the truth about the value of alternative medicine. The issue at hand is more than just academic: misleading results in health care endanger our health.

It is relatively easy to identify the problem, yet it is hard to solve it. I don’t pretend to have the ideal solution. All I can suggest is that journal editors consider making their authors’ conflicts of interest transparent and that readers of such papers apply a healthy dose of skepticism. Whenever there are two discrepant opinions (and that is the case more often than not), my advice is to determine which one might be prompted by a conflict of interest. In theory, this sounds fine; in practice, I am afraid, it will not be nearly enough to remedy the problem.

References

Bronfort, G., M. Haas, R. Evans, B. Leninger, and J. Triano. 2010. Effectiveness of manual therapies: The UK evidence report. Chiropractic and Osteopathy 18(3). doi: 10.1186/1746-13 40-18-3.

Ernst, E. 2009. Spinal manipulation for asthma: A systematic review of randomised clinical trials. Respiratory Medicine 103(12): 1791–95.

Ernst, E., and P. Canter. 2006. A systematic review of systematic reviews of spinal manipulation. Journal of the Royal Society of Medicine 99(4): 192–96.

Ernst, E., and M.H. Pittler. 1997. Alternative therapy bias. Nature 385: 480.

Han, J.S., and Y.S. Ho. 2011. Global trends and performances of acupuncture research. Neuroscience and Behavioural Reviews 35(3): 680–87.

Kaminskyj, A., M. Frazier, K. Johnstone, and B.J. Gleberzon. 2010. Chiropractic care for patients with asthma: A systematic review of the literature. Journal of Canadian Chiropractic Association 54(1): 24–32.

Schneider, C., B. Schneider, J. Hanisch, and R. Van Haselen. 2008. The role of homoeopathic preparation compared with conventional therapy in the treatment of injuries: An observational cohort study. Complementary Therapies in Medicine 16(1): 22–27.

Tang, J.L., S.Y. Zhan, and E. Ernst. 1999. Review of randomised controlled trials of traditional Chinese medicine. BMJ 319 (7203): 160–61.

Vickers, A., N. Goyal, R. Harland, and R. Rees. 1998. Do certain countries produce only positive results? A systematic review of controlled trials. Controlled Clinical Trials 19(2): 159–66.

I feel grateful and privileged that the research I have done on memory in the past three decades has been honored for its contributions to science and human welfare. But of all of these awards, this one, in honor of scientific freedom and responsibility, has a special poignancy for me. I never set out to carry the banner for those glorious words freedom and responsibility; I was merely a scientist interested in the fallibility and malleability of memory—a subject that turned out to be central to the “repressed memory” moral panic that swept this nation in the 1980s and 1990s. If anyone had told me in advance that my scientific commitment to knowledge would make me the target of organized, relentless vitriol and harassment (not to mention expensive litigation), I might have laughed at them—“Memory? Who gets angry over different memories?”

Every now and then I’d find myself wondering: If I’d known this in advance, would I have made the same decisions? Would I have decided to do the same kind of research, to spend countless hours in courtrooms testifying for the falsely accused, to write endless articles in rejoinder to dubious but persistent clinical ideas?

I do know that once faced with the choice between yielding to the wave of hostility and criticism that my research provoked or standing as strong as I could for science and justice, it was a no-brainer for me. But it was a decision that took an enormous personal toll, which is why this award is so meaningful and gratifying to me.

We live today in perilous times for science: conflicts of interest that taint research; pressures on scientists to cut corners to get fast results; a public culture that alternates between hostility to science and irrational expectations of what science can provide. If we as scientists want to preserve our freedom (and the welfare of others), now more than ever we have a responsibility.

And that responsibility is to bring our science to the public arena and to speak out as forcefully as we can against even the most cherished beliefs that reflect unsubstantiated myths.

It is not difficult to set up experiments that seemingly “prove” that bogus treatments work. Health journalists, in particular, are regularly taken in by such bogus studies, and the misleading results are subsequently reported in the press, perpetuating the public’s belief in these treatments.

I will give several examples from the realm of “alternative” medicine. They are, of course, entirely fictitious. Not that there is a shortage of real ones, but these days one has to be careful not to end up in the hands of libel lawyers (see “Keep Libel Out of Science,” SI, May/June 2010).

Bogus Experiment No. 1

Most clinical trials test whether one treatment is better than another. These studies are called “superiority trials.” Other studies are aimed at testing whether one therapy is as effective as another. They are called “equivalence trials.” My first example is an equivalence trial comparing a highly dilute homeopathic remedy with an accepted and well-known drug, say paracetamol (known in the U.S. as acetaminophen). Take two hundred patients with a sprained ankle and randomize them to take homeopathic arnica (the experimental treatment) or paracetamol (the control treatment). One or two days later, measure the swelling of the injured ankle as an undeniably objective outcome measure. The results will show that the swelling diminished in both groups and that no difference between the two groups emerged. The conclusion, therefore, is that both are equally effective; however, homeopathy (not having any actual active ingredient) caused fewer adverse events. The headline in the papers might read: “Homeopathy Better than Paracetamol.”

The trick here is to select an outcome measure that is not affected by the “accepted and well-known” drug. Paracetamol does not reduce swelling, and few people would claim otherwise. Thus, it acts as a placebo. Comparing two different placebos should always result in equivalence. Yet the illusion can be quite convincing.

Bogus Experiment No. 2

My second fictitious study is also an equivalence trial. It compares homeopathic care against conventional medicine for a serious chronic condition, say Crohn’s disease. Twenty patients are randomized to be treated with either approach. The results demonstrate that the carefully chosen endpoint (e.g., a symptom score) reveals no differences between the groups. The conclusion: homeopathy is as effective as standard treatment of Crohn’s disease. The headline this time? “Homeopathy Scientifically Proven to Work for Life-Threatening Diseases.”

The trick here is to underpower the study dramatically. Underpowered equivalence trials will tend to (falsely) suggest equivalence between the two tested approaches—a safe bet for illusionists.

Bogus Experiment No. 3

Another approach is to conduct a “pragmatic” trial. Such studies are currently very popular because, according to their proponents, they best reflect the “real life” situation of clinical practice. In this trial, chronically ill patients are randomized to receive either standard care (the control group) or standard care plus homeopathy (the experimental group). The primary measure of outcome for that study could be patient satisfaction, well-being, quality of life, or some other subjective endpoint. Due to the regular, lengthy, empathetic encounters received by the latter group, patients are bound to feel better and improve. Illusionists will then interpret this benefit as being caused by the specific effects of the homeopathic remedies. The headline: “Homeopathy Proven to Help Chronically Ill Patients.”

The trick, in this case, is that A (standard care) plus B (homeopathy) is always more than A alone (A<A+B)—unless, of course, B is zero. But an empathetic encounter does, of course, have an impact on many subjective outcome measures. If, in clinical trials, we do not control for nonspecific effects, it is always easy to make a treatment look effective, even in a randomized trial.

Bogus Experiment No. 4

My last illusionists’ stunt is an animal study. Such experiments, it is often (falsely) claimed, are not affected by placebo effects. Ten experimental rats receive a diet to which either a homeopathic product or a placebo is added. The aim here is not to test for therapeutic effects but to find out whether homeopathy can cause a biological effect in principle. All conceivable types of bias and confounding are excluded. The study can be designed to be completely watertight. The rats receive the treatments and are observed for several weeks. At the end of this period, all rats in the homeopathy group have died, but all of the control animals are alive. The conclusion: homeopathy generates biological effects and is thus different from placebo. The headline: “Animal Experiments Prove the Principles of Homeopathy.”

The trick is simple: we need only to select the right “remedy” (and “hide” this in the small print of the experiment). For my fictitious experiment, I chose a “mothertincture” of arsenic. This is pure, undiluted, and very toxic arsenic, yet it is strictly speaking a homeopathic preparation.

The conclusion? Bogus experiments are not difficult to set up, and it is not difficult to fool uncritical people with their results. But they are still only tricks of illusionists who aim to mislead us. It follows that, if we fail to apply our skills of critical assessment or, worse still, we never had such skills, illusionists pretending to be scientists can be a menace.

Skeptics are rightly challenged to assess claims made by all parties when an issue of major public importance arises. This is especially true when any action taken may have unpredictable economic consequences for the entire country. Questions related to global warming, climate change, and national energy policy represent such an issue today.

Both proponents and opponents of action are now arming themselves for a major political fight. Proponents have collected a large body of scientific evidence predicting that maintaining the status quo will consign the world to climate disaster. Opponents are arguing that an economic collapse could result from expensive, dramatic action. Some opponents also argue that we need more research. In light of this, a continuing effort for objective assessment is needed.

This year, the current administration in Washington is preparing legislation that would, if fully implemented, mandate significant reductions in carbon dioxide emissions and also collect several hundred billion dollars in carbon taxes over a ten-year period. These taxes would be collected through a mechanism known as cap-and-trade by selling carbon credits—allowances to produce carbon dioxide—to industries that generate this known greenhouse gas. President Obama has endorsed this approach, which has been in place for several years in the European Union. Not surprisingly, there are opposing views on how well cap-and-trade has worked in Europe.

In response to this legislation, proponents and opponents have embarked on a major effort in Washington to pass, modify, or defeat it. Nearly every environmental organization, the majority of scientific organizations, and most Democrats support the legislation; most spokespersons for the energy industry, some scientists, and the more conservative Republicans tend either to oppose it or at least to seek major modifications. For example, The Intergovernmental Panel on Climate Change (IPCC) Physical Science Report-2007 summarizes the work of approximately 2,000 scientists worldwide and supports major initiatives to curb carbon emissions. Representing the opposition according to Environment Maryland, a citizen-based environmental advocacy organization, are approximately 2,000 lobbyists who have been engaged by American energy industries to identify flaws in the IPCC-2007 arguments and in the administration’s legislation.

Both sides have made significant efforts to establish scientific credibility with the public. Those favoring action rely heavily on the IPCC-2007 science report and note some alarming recent research that suggests the Greenland icecap may be melting at a faster rate than even IPCC-2007 reported. In contrast, a well-known opponent of human-induced global warming, Senator James Inhofe of Oklahoma, has sought to persuade people that the current scientific majority view is misguided. (Inhofe is the ranking Republican member of the Senate Committee on Environment and Public Works.) In consequence, his office has issued a Senate Minority report titled United States Senate Minority Report on Global Warming. It can be found at epw.senate.gov.

The minority report lists a number of individuals identified as scientists who allegedly dissent over man-made global-warming claims. As of January 2009, the number of such persons listed was 687. Noting that there were indeed some quite well-known scientists on the list, and in view of the importance of the issue, the Center for Inquiry/Office of Public Policy decided to vet the list carefully to establish how credible it is overall.

This research produced the following information on the 687 people listed in the Senate minority report. Categories included name, education, summary of publications in the refereed literature based on the better-known climate science and solar physics journals, current institutional affiliations, and professional identifications.

The proportion of them who have published articles on climate science proved to be slightly less than 10 percent. Rounding off, a total of 15 percent exhibited a significant publication record in subjects at least related to climate science. We found no evidence that 551 (~80 percent) had any peer-reviewed publications bearing on climate science. At least fifty-five had no science credentials at all, and many others identified as meteorologists proved to be weather reporters. Almost 4 percent expressed support for the general consensus supporting anthropogenic causes of global warming, the near-consensus expressed by the IPCC-2007 science report, and therefore should not have appeared on the list in the first place.

How should a skeptic deal with this information? All trained scientists admit that scientific truth is ultimately probabilistic, even when the probabilities appear to be approaching certainty. It is also true that the climate scientists I know grant that there are still a few “dark corners” in the realm of cloud theory that need to be explored in more detail using new data obtained on a smaller grid. Finally, it cannot be ruled out that some as-yet undiscovered natural process may be playing a larger than anticipated role in global warming. Opponents of human causation often propose the sun as the likely driver of contemporary global warming. While no one can say with certainty that the sun plays only a small role in climate change today, as a solar physicist I can say that the various solar mechanisms proposed to date have either been discredited by current research or have been presented in highly speculative arguments not now supported by observations.

Where does this leave us? As concerned citizens we need to recognize that we are dealing with a two-step decision process. The first step is getting the science right. There is no doubt that a large majority of the scientific research community thinks global-warming-driven climate change is due primarily to anthropogenic greenhouse gases. That there remains a much smaller number of research scientists who disagree and that no one can claim certainty about this complex problem is equally true. This makes it relatively easy for those who wish to delay or prevent action to claim to the public that there is a big controversy over the science, implying that action, and especially expensive action, would be unwise. However, the evidence suggests otherwise. That there is a big and growing scientific controversy over anthropogenic sources of global warming is almost certainly untrue.

The second step in the decision process is the political one, which necessarily brings in the economic issues. This brief piece cannot address those issues except to acknowledge their critical importance. Nevertheless, we can ask the skeptic who is not acquainted with the relevant science where he or she thinks the most credible scientific assessment lies—with the scientists whose published research is reported in the IPCC-2007 science report or with the much smaller group of scientists collected for the Senate minority report.

It would be nice to think that viewers are canny enough to realize that such shows contain considerably more fiction than fact and that they might use their precognitive powers to hit the “off” button on their TV controllers before the programs begin. Unfortunately, research suggests that a significant percentage of the public really does believe that such programming depicts genuine paranormal events and thus comes away more convinced than ever about the existence of such phenomena. Perhaps because of this, various official bodies and pressure groups have urged those producing such shows to act responsibly. The Committee for Skeptical Inquiry’s Council for Media Integrity has suggested that certain paranormal programming should carry “entertainment” or “fiction” labels. Likewise, the British media regulatory body Ofcom notes that any demonstrations of paranormal phenomena “… that purport to be real (as opposed to entertainment) must be treated with due objectivity” and that if a demonstration is for entertainment purposes, “this must be made clear to viewers.”

Program creators and broadcasters usually attempt to comply with such guidelines by presenting onscreen “disclaimers,” essentially informing viewers that such shows may not be exactly as they appear and thus should only be taken seriously by the hard of thinking. However, such messages are often shown for a very short period of time and tend to contain long and rather tortuously worded messages displayed in a relatively small font. Although such disclaimers may satisfy legal and regulatory guidelines, we wondered whether they had any real psychological impact on viewers. We hypothesized that if people genuinely believed that a program containing seemingly impossible phenomena was developed to entertain rather than inform, then they should be less likely to believe that the phenomena shown constitute evidence for the paranormal. But do the types of disclaimers typically used actually affect the way people view the evidential nature of the phenomena shown?

To help find out, we conducted an initial study. We recorded a ten-minute segment from a well-known television show in which an alleged medium gave readings to various audience members. The clip ended with an eighty-word disclaimer explaining that the show should be seen as entertainment, that people varied in their opinions about the nature of alleged mediumistic abilities, and that the program content should not be construed as fact. This long paragraph was broadcast in relatively small type and remained on the screen for about ten seconds.

We showed the clip to a group of undergraduate psychology students and asked them to rate the degree to which they thought the program provided evidence of “paranormal” powers, using a scale ranging from 1 (strongly disagree) to 7 (strongly agree). Next, we created a second clip by editing out the disclaimer altogether, showed this clip to another group of students, and had them make the same ratings. There was no statistically significant difference between the two groups’ ratings, suggesting that the disclaimer had no effect on the way in which the students perceived the paranormal content of the program.¹

We wondered whether the lack of any effect was due to the disclaimer being shown at the end of the program. After all, participants had probably made up their minds about the alleged paranormal phenomena by then, and the near-subliminal presentation of the long paragraph was unlikely to influence them one way or another. To test this idea, we edited the clip yet again, this time placing the disclaimer at the start of the show. This new edit was shown to another group of students, who again went on to rate the degree to which it provided evidence of paranormal powers. The results? Once again, there was no significant difference between their ratings and the ratings of those who didn’t see the disclaimer.²

Undaunted, we toyed with the notion that perhaps the disclaimer was simply too vague and so produced our own shorter, more strongly worded, version:

The alleged mediumistic abilities of the individuals featured in this program have not been subjected to controlled scientific investigations. In addition, some scientists have suggested that anecdotal evidence in support of such abilities could be due to several psychological techniques, such as use of general statements and feedback from people’s verbal and non-verbal behaviour.

Once again, this was placed onscreen for ten seconds. We showed this version to two more groups of students, with one group seeing it before the show and another after. Did this have any effect? No. Once again, there was no statistical difference between the ratings of these groups and the ratings of those that saw no disclaimer at all.³

At present, we don’t know why the type and position of the disclaimers tested have no significant effect on the way in which people view the evidential nature of the alleged paranormal phenomena in the program. It could be, for example, that our participants couldn’t be bothered to read the disclaimer or that any influence it had was outweighed by the much more dramatic material in the rest of the clip. Either way, the results suggest that there is a pressing need to develop a form of wording and presentation that really gets the message across. Until then, the situation remains grim. Next time you see a paranormal program briefly presenting one of those long “for entertainment only” disclaimers you might be tempted to think, “Oh well, I guess it’s better than nothing.” Our research suggests that you are wrong.

Notes

1. Original disclaimer at end (N=25), mean evidentiality rating = 2.71; no disclaimer (N=25) mean evidentiality rating = 2.59; t(51df) = .255, p = .80.
2. Original disclaimer at start (N=29), mean evidentiality rating = 2.59, t(54df) = .014, p = .99.
3. New disclaimer at start (N=31), mean evidentiality rating = 2.83, t(57) = .510, p = .61; new disclaimer at end (N=26), mean evidentiality rating = 3.2, t(52df) = 1.247, p = .22.

Dieguez claims (without giving evidence) that the targets are not kept blind or randomized properly. If he’s right the experiments are worthless, but let us suppose they are done properly. Anecdotal reports of veridical NDEs may be “unconvincing” to Dieguez, but they convince many people. So if experiments can show that paranormal claims are unverifiable (which I expect they will) and can also explain why people have these experiences even if nothing leaves the body, then this would greatly improve people’s understanding of death and dying. Alternatively, if experiments show that people really do see hidden targets (which I do not expect but could conceivably happen), then this would be a dramatic challenge to most of science. The comparison with the intelligent design debate is false. ID proponents do not propose viable experiments that could potentially provide such a challenge.

As for ethics—yes, Dieguez is “overreacting a little bit.” The targets cannot harm patients (unless you believe in the paranormal). The critical point is when the doctor asks whether the patients would like to talk about their experiences. As long as they are given the chance to talk (as many like to do) or to decline to say anything at all then I see no serious ethical problem.

I want these experiments to be done. All those millions of people out there who proclaim they “know” they have a spirit that will survive death and “know” that consciousness has powers beyond the body deserve to have their claims tested.

First, the argument rests on the assumption that the outcome is already known, i.e., none of the patients will correctly describe the hidden target. While it is clear from my own writings on this topic (e.g., French 2005, in press) that I think this is almost certainly true, I think it is important for skeptics to acknowledge that they just might be wrong.

Second, a reasonable case can be made that there is a risk attached to not asking such patients about any unusual experiences they may have had during their cardiac arrest. Many patients report that they find it very stressful trying to talk to people about their NDEs, worried that others will think they are “crazy.” There is some value to patients being reassured that such experiences are fairly common and are not associated with mental illness.

Third, this line of argument, if taken to its logical conclusion, would seem to have implications for other lines of research involving autobiographical memory of all kinds. For example, memory of dramatic news events (so-called “flashbulb memories”) have been much studied by psychologists. Is it really the case that a psychologist studying such memories has actually started the experiment from the moment that the dramatic news event in question occurs as opposed to the moment she questions her participants about their memory of the event? I would say not.

References

• French, C. C. 2005. Near-death experiences in cardiac arrest survivors. Progress in Brain Research 150, 351–367.
• —. (in press). Near-death experiences and the brain. In C. Murray (ed.). Psychological Scientific Perspectives on Out-of-Body and Near-Death Experiences. New York: Nova Science Publishers.